The role of endoscopic endonasal salvage surgery in recurrent or residual craniopharyngioma after a transcranial approach: a systematic review.

BACKGROUND: The management of craniopharyngiomas is challenging due to their high rate of recurrence following resection. Excision of recurrent tumors poses further surgical challenges due to loss of arachnoidal planes and adherence to anatomical structures. The endoscopic endonasal approach (EEA) offers a favorable alternative to transcranial approaches for primary craniopharyngiomas. However, the safety and efficacy of EEA for recurrent tumors, specifically after a prior transcranial approach, needs further investigation. METHODS: We performed a systematic review using PubMed to develop a database of cases of recurrent craniopharyngiomas previously treated with a transcranial approach. RESULTS: Fifteen articles were included in this review with a total of 75 cases. There were 50 males and 25 females with a mean age of 38 years (range 2-80). One prior transcranial surgery was done in 80.0% of cases, while 8.0% had two and 12.0% had more than two prior surgeries. Radiotherapy after transcranial resection was given in 18 cases (24.0%). Following EEA, vision improved in 60.0% of cases, and vision worsened in 8.6% of the cases. Of cases, 64.4% had pre-existing anterior hypopituitarism, and 43.8% had diabetes insipidus prior to EEA. New anterior hypopituitarism and diabetes insipidus developed in 24.6% and 21.9% of cases, respectively following EEA. Gross total resection (GTR) was achieved in 64.0%, subtotal resection in 32.0%, and partial resection in 4.0% revision EEA cases. GTR rate was higher in cases with no prior radiotherapy compared to cases with prior radiotherapy (72.0% vs 39.0%, p = 0.0372). The recurrence rate was 17.5% overall but was significantly lower at 10.0% following GTR (p = 0.0019). The average follow-up length was 41.2 months (range, 1-182 months). CONCLUSION: The EEA can be utilized for resection of recurrent or residual craniopharyngiomas previously managed by a transcranial approach.

Mispatterning and interneuron deficit in Tourette Syndrome basal ganglia organoids.

Tourette Syndrome (TS) is a neuropsychiatric disorder thought to involve a reduction of basal ganglia (BG) interneurons and malfunctioning of the BG circuitry. However, whether interneurons fail to develop or are lost postnatally remains unknown. To investigate the pathophysiology of early development in TS, induced pluripotent stem cell (iPSC)-derived BG organoids from TS patients and healthy controls were compared on multiple levels of measurement and analysis. BG organoids from TS individuals manifested an impaired medial ganglionic eminence fate and a decreased differentiation of cholinergic and GABAergic interneurons. Transcriptome analyses revealed organoid mispatterning in TS, with a preference for dorsolateral at the expense of ventromedial fates. Our results point to altered expression of GLI transcription factors downstream of the Sonic Hedgehog signaling pathway with cilia disruption at the earliest stages of BG organoid differentiation as a potential mechanism for the BG mispatterning in TS. This study uncovers early neurodevelopmental underpinnings of TS neuropathological deficits using organoids as a model system.

Role of SHH in Patterning Human Pluripotent Cells towards Ventral Forebrain Fates.

The complexities of human neurodevelopment have historically been challenging to decipher but continue to be of great interest in the contexts of healthy neurobiology and disease. The classic animal models and monolayer in vitro systems have limited the types of questions scientists can strive to answer in addition to the technical ability to answer them. However, the tridimensional human stem cell-derived organoid system provides the unique opportunity to model human development and mimic the diverse cellular composition of human organs. This strategy is adaptable and malleable, and these neural organoids possess the morphogenic sensitivity to be patterned in various ways to generate the different regions of the human brain. Furthermore, recapitulating human development provides a platform for disease modeling. One master regulator of human neurodevelopment in many regions of the human brain is sonic hedgehog (SHH), whose expression gradient and pathway activation are responsible for conferring ventral identity and shaping cellular phenotypes throughout the neural axis. This review first discusses the benefits, challenges, and limitations of using organoids for studying human neurodevelopment and disease, comparing advantages and disadvantages with other in vivo and in vitro model systems. Next, we explore the range of control that SHH exhibits on human neurodevelopment, and the application of SHH to various stem cell methodologies, including organoids, to expand our understanding of human development and disease. We outline how this strategy will eventually bring us much closer to uncovering the intricacies of human neurodevelopment and biology.

Early developmental asymmetries in cell lineage trees in living individuals.

Mosaic mutations can be used to track cell lineages in humans. We used cell cloning to analyze embryonic cell lineages in two living individuals and a postmortem human specimen. Of 10 reconstructed postzygotic divisions, none resulted in balanced contributions of daughter lineages to tissues. In both living individuals, one of two lineages from the first cleavage was dominant across tissues, with 90% frequency in blood. We propose that the efficiency of DNA repair contributes to lineage imbalance. Allocation of lineages in postmortem brain correlated with anterior-posterior axis, associating lineage history with cell fate choices in embryos. We establish a minimally invasive framework for defining cell lineages in any living individual, which paves the way for studying their relevance in health and disease.

Metacognition, Formative Assessment, and Student Perspective: Learning About Metacognition Through In-Class Comparison of Response Systems.

PURPOSE: Educators influence learning context through, among other things, triadic reciprocal causation-a behavioral model used in social cognitive theory. Eliciting responses from learners during instruction may contribute to learning by engaging their metacognition. In this study, metacognition was examined based on learners' experience with 2 different polling methods: student response systems (SRS), commonly known as "clickers," and a low-technology response system (LTRS), where students raise labeled signs, each with a different response. Scale item results are reported. METHODS: Scales measuring the influence of metacognition from polling methods were administered, following treatment (SRS) and comparison method (LTRS), to first-year physician assistant (PA) students (n = 54). Statistical tests of significance and effect size for each item were compared. RESULTS: Performance outcomes suggest that the SRS enhances learning experiences more than low-technology polling. Self-reported surveys indicate that self-monitoring, note-taking, and understanding during lectures are significantly improved with the use of clickers. Peer and social comparison items did not demonstrate significance collectively, but survey results indicate that candidates compared themselves to their peers significantly more with the LTRS than with the SRS. CONCLUSION: Findings support the practice of using an electronic SRS to poll PA students and enhance learning.

The benefits and challenges of providing nursing student clinical rotations in the intensive care unit.

The goal of providing a clinical rotation in a basic nursing program is to integrate skills and knowledge from the classroom setting into the clinical practice setting. In the intensive care unit (ICU), nursing students have the ability to learn about the complex health issues of critically ill patients, practice selected technical skills, and develop communication skills. There are both benefits and challenges to having nursing students in the intensive care setting. With preparation, the student is able to immerse in the ICU environment, acquire new knowledge and skills, and participate alongside the nurse caring for critically ill patients. The staff nurse must balance patient care with the added responsibilities of helping the student meet the clinical goals. It is optimal to have faculty that are also intensive care clinically competent and can facilitate the clinical experience. The school, the hospital, and the ICU need to collaborate to provide a positive clinical experience that is safe for the patient. In return, the hospital can recruit student nurses and clinical faculty. Planned with thought and intention, rotations in the ICU can be an ideal clinical setting for upper-level student nurses to learn the role of the registered nurse.